Stock has appeared sporadically on the website over the last week or so, but each time it quickly sells out.

M&S is saying the items will appear gradually over the next couple of weeks.

The range includes larger versions of the bodysuits, sleep suits and vests that already exist and prices range from £3 for a sleeveless bodysuit to £7 for a sleepsuit.

An M&S spokesperson said: “We always listen carefully to our customers and our kidswear team worked in close consultation with Ms Kutt and other families on adapting some of our kidswear products to meet their needs.

"The range currently comprises a small number of products that will be available online in the next few weeks - as with all new ranges, we will closely monitor customer interest and listen carefully to customer feedback on how it should develop in the future.”